RFR: 8342465: Improve API documentation for java.lang.classfile [v2]

[Chen Liang]

> This is the last piece in the API documentation improvement of the Class-File API.
> 
> This includes general documentation about transforms, models (and traversals), options, constants, and CodeBuilder factories.  In particular, this preserves the package summary to avoid extra disruptions.  See the APIDiff for more details.
> 
> Please forgive this messy commit history; the work began before attribute changes were integrated and based off that, and in the process there were a few merges back and forth.
> The files changed/webrev should be reliable.
> 
> Please review the associated CSR as well.
> 
> Note that this intends to be backported to 24; this won't be clean, as the `JAVA_25_VERSION` constant is a new addition that does not exist on 24.
> 
> Testing: Tier 1-3.
> 
> APIDiff: https://cr.openjdk.org/~liach/apidiff/cf-overall/java.base/java/lang/classfile/package-summary.html
> Javadoc: https://cr.openjdk.org/~liach/javadoc/cf-overall/java.base/java/lang/classfile/package-summary.html

Chen Liang has updated the pull request incrementally with one additional commit since the last revision:

  Better specification of range of u2 values, flag masks and versions

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/23277/files
  - new: https://git.openjdk.org/jdk/pull/23277/files/d4b1c1ed..9fd144c9

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23277&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23277&range=00-01

  Stats: 21 lines in 10 files changed: 12 ins; 0 del; 9 mod
  Patch: https://git.openjdk.org/jdk/pull/23277.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23277/head:pull/23277

PR: https://git.openjdk.org/jdk/pull/23277